Abstract:
ML2N2O is the EOS Aura Microwave Limb Sounder (MLS) standard product for nitrous oxide derived from radiances measured primarily by the 640 GHz radiometer (Band 12) until August 6, 2013, after this date using the 190 GHz radiometer (Band 3). The current version is 2.3. Spatial coverage is near-global (-82 deg. to +82 deg. latitude), with each profile spaced 1.5 deg. or ~165 km along the orbit ... track (roughly 15 orbits per day). The recommended useful vertical range is from 100 to 1.0 hPa, and the vertical resolution is between 3 and 6 km. Users of the ML2N2O data product should read section 3.15 of the EOS MLS Version 2.2 and 2.3 Level 2 Data Quality and Description Document for more information (http://mls.jpl.nasa.gov/data/v2_data_quality_document.pdf).

The data are stored in the version 5 EOS Hierarchical Data Format (HDF-EOS5), which is based on the version 5 Hierarchical Data Format, or HDF5. Each file contains two swath objects (one with profile data, the other with column data), each with a set of data and geolocation fields, swath attributes, and metadata. The data fields include the geophysical parameter values and precision (standard deviation), convergence values, data quality, and a status flag. The geolocation fields include a time stamp in TAI-93 format (seconds since January 1, 1993), geodetic latitude and longitude, and pressure level values, as well as local solar time, solar zenith angle, line of sight angle, and orbit geodetic angle. There is one file per day.